Wall finish



Sept. 20, 1938. 0, vl MCGRx-:w 2,130,357

WALL FINISH Filed March 12, 193'? g5/Ua?? ema/Jion Patented sept". 2o, 193s yPATENT OFFICE WALL FINISH Orville V. McGx-ew, Chicago, Ill., assignor to McGrew Paint & Asphalt Co., a corporation of.r

Illinois Application March 12, 1937, Serial No. 130,609

'l Claims.

This invention is a wall coating for buildings and is fully described herein.

In practicing it, I prefer to use the composition described in detail in my pending applica- 5 tion filed December 10, 1936, Serial Number 115,254. 'I'his composition is composed largely of particles of cork and a cut-back asphalt binder of a type having a high melting point and a low temperature susceptibility, and possessing, after drying out, considerable permanent ilexibility. That particular composition has a very low heat conductivity and hence excellent insulating properties.

As far as concerns the present invention, however, the composition can be varied considerably, other solids such as sawdust, mica, etc., being used where heat insulation is less important. The asphalt mixture, toc, can be considerably varied provided the desired qualities are maintained.

The present wall coating is applicable to walls of almost any material. In frame constructions, newly built, it will normally be applied over the usual sheathing, clapboards or the like being omitted. For re-surfacing old buildings the pres ent coating may be applied over the old clapboards. The coating may be applied to metal, tile, or concrete or brick with equal facility.

The invention as illustrated diagrammatically in the drawing in which Figure 1 represents a wall having a coating of asphalt containing cork, upon which is a layer of roofing granules.

Figure 2 represents another modification in which a relatively thin layer of asphalt emulsion is applied to the cork containing asphalt and the asphalt emulsion is then covered with a coating of paint.

In carrying out the invention, the wall is first coated with a layer of the asphalt mixture selected, preferably, as above stated, that of the application referred to. 'Ihis coating is made about half an inch thick, and may be sprayed on as described in the application referred to, or may be trowelled. It adheres firmly to the wall structure without the need for any interlocking or lath-like devices.

The layer thus provided is substantially gas and moisture proof and, in the preferred composition, insulates eiiiciently. However, the outer surface it provides is quite unacceptable, both because of its unattractive color, and because of the tackiness it may develop in hot weather.

Prior eorts to use layers of such material in 55 walls have involved supplying some outer layer (Cl. 'ZZ-123) fastened through the asphaltic mass to the underlying wall structure. This has impaired the unbroken tightness inherent in the asphalt material, has provided openings which 'could enlarge under slight movement of the parts in storms and under temperature changes and the integrity of which could be greatly reduced by corrosion of the fastening devices.

In accordance with the present invention an outer ornamental and protective layer is secured by adhesion only to the asphalt layer. One excellent outer layer may be provided by coating the asphalt with roofing granules or grit which is now available in a Wide variety of colors. When this alternative is adopted, the grit is applied Vby spraying while the asphalt is fresh and soft enough to hold it. The grit may cover the whole surface or may be applied through a stencil to leave black asphalt lines simulating the joints oi brick-work. In either case the grit layer allows drying and hardening to proceed under it.

Or the asphalt layer may be permitted to dry for twenty-four hours more after which it will take a coat of paint whose base is compatible with the asphalt.

In either event, a coat of asphalt emulsion may be applied to the asphalt layer below the paint coat. 'Ihis is not necessary, but it provides a perfect seal to any accidental pores which may have been formed in applying'the main coat, and affords a highly tenacious bond with the iinish coat.

The wall coating provided as described has numerous advantages. It is far cheaper than any other acceptable outer coating, and it can be applied to either old or new structures with great ease and with the absolute minimum of preparation of the underlying surfaces.

When completed, the walls are of excellent appearance, and, in case grit is used, are extremely durable, requiring no attention over many years. The coating is not greatly affected by temperature changes, and is flexible enough not to crack under the minor movements which occur in storms. It provides a practically hermetic seal, and is most useful when, as in some air conditioning systems, it is desired to control ac curately the entrance of air to a building and to eliminate leaks.

It is especially noteworthy that the asphalt layer is not only somewhat yielding but is not pierced by nails or other fasteners. Under expension and contraction from temperature changes, and the weaving which occurs under wind pressure, fastener holes always enlarge and most fasteners corrode so that the complete tightness of the building is greatly decreased. The present wall, on the contrary, remains absolutely tight for many years.

What I claim as new and desire to secure by Letters Patent is:

1. In a wall, an imperforate coating composed of inert solid particles bonded together and having interstices lled by a permanently flexible asphalt binder o! high melting point and low temperature susceptibility, said coating being secured to the underlying wall structure solely by adhesion, and a yielding outer non-asphaltic outer coating exposed to the weather and secured to the ilrst named coating solely by adhesion.

2. 'I'he structure of claim 1 wherein the solid particles are largely cork.

3. The structure of claim 1 wherein the outer coating is grit particles.

4. The structure ot claim 1 wherein the solid particles are largely cork and the outer coating is grit.

5. The structure of claim 1 wherein the outer coating is a paint whose base is compatible with asphalt.

6. The structure of claim 1 having a coating of asphalt emulsion between the asphalt layer and the outer coating.

7. In a wall an imperforate coating having a thickness of the order of one-half inch composed of inert solid cork particles bonded together and having interstices illled by a permanently flexible outback asphalt binder of high melting point and low temperature susceptibility, said coating being secured to the underlying wall structure solely by adhesion, and a yielding outer coating exposed to the weather and secured to the first named coating solely by adhesion.

ORVILIE V. MCGREW. 20 

